Boiler fusible plug.



W. F. RAY & R. BONNETT. Boum FuslB'LE PLUG.

FILED APR.9. |91

9237,957., Patented Ag. 21,1917.

.inspection regulations that. the yplitg shall project into the Water acertain .specified shell, the deposit :quently, t thimble' noinnrnsienn rLue.

Specification of Letters Patent.

Patented Aug. 2f, 319317.

Applcationiled April 9, 1915. vSerial No. 20,313.

To all lwhom if may concern f Be it known 4that-we, lViLLIAM F..RA=Y and ROBERT BONNETT, citizens of the United Statearesiding at Samoa, in fthe county of `lliiinboldt,vfitate of California, havel invented, a new and useful BoiierFusible plug, offwhicli `the followingiisa specifica tion.

- :The device` forming they subjectimatter of this. application is a soft plug foricrown sheets, boilersland `the like, and yinorder that the advantagesfiof the presentinvenf tion may be apparent readily,

distance, `and as a consequence,;the projectingend ofi the thiniblefsoon becomes incruste-d with linie or other materialiderived from `the water. @When thevtliiinble is threaded out of the crown sheet orboiler destroys the threads in thecrown sheetor shell to such an extent ceiving opening must be rethreaded and, freit fis necessary or plug @1in order that the saine '.inaycoperate properly with `.the rethi'eaded `that end of the tliiinble yjects into the water,

nietalp that the thinible threaded out Without difficulty, thefire end` opening. A

ln `view of the foregoing, one object of the present invention is to provide novel ineans'whereby the `threads of the thiinble, upon that end ofwthe thiinble which prowill be protected.` in devices of tliis;soi't,`the fire end of the thinible which carries the fusible'nietal, generally projects intoxthe furnace and soon becomes deteriorated to such an extent that the thimble, or plug eannotbe threaded out of the shellby applying .a wrench to Whicliprojects into efurnace. f

Another object of the invention,` theref Fig. 3 is an elevation of fore, is so. to house` andy protect theiireend of `the thiinble `which carries the fusible may atall 4times be of ythe tliinible being so constructed tha such aresult may be brought about.-` j

ln order that the thiinble may be rotated readily, the saineis provided at its lireend ble metal in itheithiinble is Athatend of the plug of tliesoit liereindei ated.

1 toprovide a means for onthat end of the thiinble which projects of the crown sheet or ymeans whereby the thinible may be rotated on ythe thiinble frequently r i that the thiinble reg to makeya special yto `improve generally. andl ',merall indicates a portion the water numeral 3 with a kerf adapted to receive screw-driver or like tool. The mass of fusiset back lfrom thimble which carries the kerf and as a consequence, the end of the `mass of. metal is not intersected by the. kerf.

Oneendy face of the mass of metal, therefcre,freinains continuous and unbroken and is adapted to Y,receive an inspectionstainp whichncoinmonly is placed upon both ends ofv` the `mass of metal.

the fact that one end of the mass of metal is /heieinbefore stated, the stainp receiving face prominently to the fire and not be likely to be obliteris not presented the stamp will Tlie'invention, generally considered, aims protecting the threads into the Water space, to provide novel means for alining one end face of the tliimble and one end` of the socket with the fire surface shell, to provide novel f the mass of fusible metal is shielded and protected against(deterioration dueto furnace heat.

:It is Within the province ofthe disclosure to enhance the utilityof'idevices of that type to which the present invention,appertains l/Vith the above and other objects in view ywhich will appear as the description proceeds, the invention resides in the combination and arrangement of` parts and in the details of construction hereinafter described and claimed,4 it being understood that a heavy y,

Further, `owing to A changes `in the precise embodiment of the t invention herein disclosedA can be made within the scope of `what is claimed, without departing' from the spirit of the invention. ,In the accompanying drawings Figure l shows tudinal section FiggQ is a bottom plan;

a tool employed for seating lthe socket in place.

In the accompanying drawings, the nuof a crown sheet, side of which is denoted by the and the lire side of which-is denoted by the numeral 2.

`f llie numeral i indicatesa socket Lwhich the invention in longiv.

j one end of the socket is flush zingy av tapered driveror .like tool. One end kcontinuous and y as well as the opposite end face of the mass vin Fig. 3, wherein there appears 192-s a shoulder ythe head f endface of the socket and preferably is fashioned from steel oriron. The socket4 is externally threaded as shown at 5 to engage with may if desired have as clearly shown in Fig. 1. In one end yof the socket 4 there is formed a recess 6, delfning within the contour of the socket, a` cirthe Vshoulder, the bore of the socket 4 is reduced in diameter, Vtapered and threadedas shown at8.`. ff. Y i

The ,invention comprises a thimble -9 havbore 10.

the recess 6 of the socket.

11v `received in vBeyond the head 11, the thimble 9 is tapered tofor-m a neck 14 threaded'to engage with the threadedportionS of the boreofthe socket 4. The thimble 9r may be made of brass or some other metal which expands at a lower degree of heat than does the metal out of which the socket 4 ismade.

Located in the bore 10 of the thimble 9 is a mass of fusible metal indicated at 15. In one end of the thimble 9 there. is formed a kerf 16 adapted to receive a heavy screwy face v1"( Y of the mass 15 of fusible metal is set back from the re surface 2 of the crown sheet toa vpoint adj acentthe base of the kerf 16. rl`he end face 17 of the mass of metal, therefore, is not intersected by the kerf 16 and remains unbroken, the end face 17 of fusible metal 15 being adapted to be stamped as is the common custom with boiler inspectors. Y f An important although not mandatory adjunct to the present invention `is disclosed an apply- 1S having a threaded portion 20 and ya wrench head 21.

n assembling `the invention lwith the crown sheet 1 as shown in Fi 1, the socket 4 is threaded onto the part 19 of the applying member 18, the shoulder 2O in the applying memberabutting against-the shoulder in the socket. A wrench is then applied to 21 and the socket is threaded into the crown sheet as shown in Fig. 1, until with the re surface 2 of the crown sheet. The applying member 18then is removed from the socket. Thereupon the thimble 9 is threaded into the socket, a screw-driver or like tool being inserted into the kerf 16, the tapered, threaded neck 14 of the thimble binding tightly in the tapered, threadedl bore S of the socket and inof member v the end face 12 of the thimble being disposed approximately flush with the corresponding with the re surface 2 of the crown sheet 1. The parts thereupon will appear assembled as shown in Fig. 1.

Sincethe thimble 9 is fashioned from the crown sheet 1 vand` a slight external taper,

' 'pansion,

-At one end, t e f thimble 9 is' provided with v an venlarged head face 17 is not vintersected crown sheet having va the threaded opening in the 7 threaded into some metal which expands more readily under heat than does the metal out'of which the socket 4-is formed, the' head 11 of the thimble will soon acquire, under heat exa tight fit against the lateral wall of the recess 6.

The threads on the exterior of the thimble `9 are protected by the socket 4 and cannot become encrusted with lime or the like. Therefore, the removal of the thimble 9 is 'la matter which can be carried outwithout difficulty. Y Y.

@wing to the fact that Vone end face of the thimble 9 and the corresponding sheet 1 there; are no parts projecting into the furnace and likely f to melt or becomev deterioratedfespecial at,-

vtention being `face 17v of the mass 15 offfusible the'fire surface-2 of crown sheet and will not deteriorate due to heat and, it is to be noted, the said en by the kerf 16 and therefore remains continuous and yunbroken, and is well kadapted to receive an inspection stamp.

end face of the socket 4 are iush with theV fire surface 2 of the crown directed tothe manner'y in rwhich the kerf 16 is housed and protected.

lt will be obvious to thoseskilledin. the

art that* the entire structure shown in Fig. 1 will be employed in inverted position if the water is below the sheet 1 andthe ire is above the sheet. .j

Having thus described the invention, what is claimed is 1. Ina device of the class described, :a threaded opening; a socket externally threaded to cooperate ywith crown sheet and having its .fire end disposed flush with the re side of the crown sheet, the socket bein provided'in its ywater end with a threade bore, and being provided in its fire end with an enlarged, smooth, cylindrical recess'dening a shoulder adapted to receive an applying tool whereby the the opening in the crown sheet; a ythimble having a screw driver kerf in its iire end and having a Haring bore, the thimble being provided at its re end with a smooth head received in the recess and Viiush with Vthe ire end of'thesocket, lthe socket i may be mass ofk fusible metal located inthe bore of the thimble and terminated adjacent the base-of the screw driver kerf.

2. Ina device of the class described, a crown sheety having a threaded opening which is tapered from the fire side of the sheet to the water side thereof; a socket externally threaded and tapered continuously from its fire end to its water end, the socket being mounted in the threaded-opening of the Ycrown sheetand havingitsire end disposed Hush with the fire side of the crown minating in :L tapered, externally threaded Sheet, the socket being provided in its water neck eoaeting with the tapered bore of the 15 end Awith a tapered threaded bore, and being' socket; and a mass of fusible metal located provided in its fire end with en enlarged, in the bore of the thinibie and terminated smooth, oyiinvflricel recess defining d shouledjecent the base of the screw driver kerf.

der adapted to receive an applying tool In testimony that We claim the foregoing whereby the socket may be thremed into the es our ovvn, We have hereto ehxed our slg- 20 opening in the Crown sheet; a tbimble havnatures in the presence of two Witnesses.

ing :t screw driver kerf et its fire end and WILLIAM F. RAY. having :i bore, the thiinble being provided ROBERT BONNETT. at its fire end with a. smooth head received Witnessess in the recess and flush with the re end of G. J. SPEER, Jr.,

the socket, the Water end of the thimble ter- G. A. STUART Copies of this patent may be obtained for ve cents each, by addressing the Gommissioner of Patents. Washington, ID. C. 

